Nitrogen- and sulfur-containing hydrocarbon and polymeric compositions have been shown to possess useful properties in a broad range of applications. Several of these sulfur- and nitrogen-containing hydrocarbon compositions are known to have beneficial properties when adapted for use as additives in hydrocarbon fuel and lubricating oil compositions. Such compounds of low molecular weight, such as above about 250 and below about 5,000 number-average molecular weight (M.sub.n), or below about 10,000 weight-average molecular weight (M.sub.w), have shown utility as additives in both hydrocarbon fuels and lubricating oils whereby enhanced anticorrosion, oxidation inhibition and/or dispersancy activity are imparted to these hydrocarbons. When of high molecular weights, such as above about 5,000 M.sub.n or 10,000 M.sub.w, such compounds are known to impart viscosity index (V.I.) improving properties to lubricating oil composition in addition to the properties exhibited by the low molecular weight compounds.
For example, it is known that multifunctional viscosity index improvers containing nitrogen have enhanced dispersant activity. In particular, polymeric nitrogen-containing substances are known to be useful as lubricating additives, with detergent-dispersant and other properties. For example, U.S. Pat. No. 4,194,984 teaches the incorporation of ethylenically unsaturated, nitrogen-containing organic reactants onto substantially saturated hydrocarbon backbone chains with side chain unsaturation. In particular, this patent discloses the incorporation of acrylonitrile onto terpolymers of ethylene-propylene and 5-ethylidene-2-norbornene by a thermal ene reaction. The product disclosed in this patent is said to be a dispersant when having an M.sub.n of from about 1,000 to 10,000 and to be a viscosity index improver with dispersant-detergent properties when having an M.sub.n of from about 10,000 to 200,000. This patent specifically discusses the benefits of a thermal addition as compared to the free radical copolymerization or grafting of nitrogen-containing compounds with or onto V.I. improving polymeric substances. It also suggests the inclusion of sulfur atoms in the nitrogen-containing ethylenically unsaturated reactants, but does not suggest the addition of any reactants which have one or more reactive sulfur-to-nitrogen unsaturated sites to any hydrocarbon backbone chain.
It is also quite well known in this art to incorporate sulfur-containing compounds into lubricating oil additives for the purpose of improving the oxidation properties of crankcase lubricants, for example. As an example, U.S. Pat. No. 4,177,153 teaches the use of oil-soluble sulfurized olefins with oil-soluble tertiary amines for additive compositions providing improved anti-oxidant properties. This reference, however, does not suggest the thermal incorporation of a single unsaturated sulfur- and nitrogen-containing reactant onto a hydrocarbon compound.
It is also known in the art to sulfurize nitrogen-containing multifunctional additive polymers. The resultant nitrogen and sulfur-containing compositions have been shown to possess antioxidant, oxidation or thermal stability and corrosion-inhibiting properties, in addition to their dispersant-detergent properties at low molecular weights and V.I. improving properties at higher molecular weights. For example, U.S. Pat. No. 3,390,086 teaches the treatment of certain ashless dispersants, including aminated low molecular weight polyisobutenyl succinic anhydrides, with elemental sulfur to improve thermal stability for high temperature uses. In addition, U.S. Pat. No. 3,309,316 teaches the sulfurization of an alkenyl substituted succinic anhydride by reacting first with elemental sulfur and then with a polyalkylene polyamine. The sulfur and nitrogen-containing products of this patent are said to possess corrosion inhibition properties, detergent-dispersant properties when of low molecular weight and, with higher molecular weight olefin polymers as the alkenyl substituent, may impart V.I. improving properties. Also, U.S. Pat. No. 3,200,107 teaches a process for preparing a multifunctional additive of hydrocarbon compositions wherein an alkylene polyamine is reacted with carbon disulfide and with a hydrocarbon-substituted dicarboxylic acid or its anhydride. The preferred low molecular weight product contains both nitrogen and sulfur, and possesses antioxidant, detergent and corrosion-inhibiting properties, and when of high molecular weight possesses V.I. improving properties. However, none of these references suggests the direct thermal addition of a single sulfur- and nitrogen-containing compound onto a hydrocarbon compound.
The reaction of certain sulfur- and nitrogen-containing inorganic thiocyanate salts with alkenyl compounds to produce sulfur- and nitrogen-containing organic compounds which are useful as additives in hydrocarbon compositions is also known. For example, U.S. Pat. No. 4,303,539 teaches the preparation of thiocarbamyl derivatives from the reaction of previously prepared alkenyl isothiocyanates with amines, alcohols or thiols, these derivatives having utility as additives for fuels and lubricating oils for enhanced anticorrosion, oxidation inhibition and dispersancy activity. Specific alkenyl isothiocyanate precursors include octadecenyl isothiocyanate, polyisobutenyl isothiocyanate, poly(ethylene-propylene-1,4-hexadiene)isothiocyanate, poly(ethylene-propylene-2,5-ethylidene norbornene)isothiocyanate, etc. However, this patent does not suggest the direct thermal addition of reactants with one or more reactive sulfur-to-nitrogen unsaturated sites to unsaturation in hydrocarbon compounds.
The cyclic addition of a sulfur monoimide at unsaturated sites in steroids for pharmaceutically useful compositions is disclosed in U.S. Pat. No. 4,342,754 which teaches the incorporation of N-sulfinyl carbamates with 17-alpha-alkylaminoethyl-17-alpha-hydroxysteroid to create steroid-spiro-oxathiazolidine derivatives having antimineral cortisoid effects. This cyclic addition does not involve hydrocarbon compositions exhibiting usefulness in polymers or oleaginous composition applications.
Thermal addition reactions of nitrogen and sulfur containing N-sulfinyl urethanes and sulfur diimides with alkadienes and alkenes have been the subject of discussion in some areas of the scientific literature. For example, in the Angew. Chem. Inter. Edition/Vol. 6 (1967)/No. 4 by H. H. Hoerhold, there is a description of the synthesis of N-sulfinyl urethanes, and mention of reactions in which a 1,4-addition of N-sulfinyl urethane occurs with norbornene and a cyclic addition occurs with 1,3-dienes; and in "Bis(methoxycarbonyl)Sulfur Diimide, a Convenient Reagent for the Allylic Amination of Alkenes," J. Org. Chem. (1983), pages 3561-3564, by G. Kresze and H. Munsterer, the synthesis of bis(methoxycarbonyl)sulfur diimide is described, as is its ene reaction with alkenes at ambient temperatures or below to form intermediate diamino sulfanes that can be further transformed into carbamates by treatment with hydroxides at room temperature. These cases, however, do not even discuss the potential utility of any of the products of these reactions, and they certainly do not suggest the reactions of these unsaturated sulfur- and nitrogen-containing compounds with oil soluble hydrocarbon compounds having ethylenic unsaturation to form products useful in polymeric or oleaginous composition applications.